DelayedHud3<T1, T2, T3> class Null safety

In the following example, we will use a ChangeNotificationProvider to trigger showing the HUD. It is also using a delayed start. When one of the providers change values, the callback showHud will be called and the providers will be passed to this function. You can then check its value to determine if you need to show the HUD.

  hud: hud,
  child: Text('DelayedHud1<TestViewModel, AnotherViewModel, YetAnotherViewModel>'),
  delayedStart: delay,
  showHud: (viewModel1, viewModel2, viewModel3) {
    return viewModel.isBusy || viewModel2.isSaving || viewModel3.isProcessing;


DelayedHud3({Key? key, required Widget child, Color? color, Widget? hud, Duration? delayedStart, Widget hudWidget(T1 value1, T2 value2, T3? value3)?, required bool showHud(T1 value1, T2 value2, T3 value3)})
Constructor, only the child attribute is required.


child Widget
Widget that will be rendered by the HUD. Ideally this widget is a scaffold so when the HUD is rendered it covers the entire screen.
color Color?
This is the color used to cover the screen in between the child and the HUD control. If you don't specify this value, a translucent black color will be used.
delayedStart Duration?
Duration that the HUD will wait before you show it. If null, it starts automatically. Ideally, consider a duration of 250ms.
hashCode int
The hash code for this object.
hud Widget?
Widget that is rendered when a HUD needs to be displayed. Typically this would be a CircularProgressIndicator()
hudWidget → (Widget Function?(T1 value1, T2 value2, T3? value3)?)
This is an alternative to the hud attribute. This is a callback that lets you generate a Widget using the various providers used. This gives you additional context in case the HUD is context aware.
key Key?
Controls how one widget replaces another widget in the tree.
runtimeType Type
A representation of the runtime type of the object.
showHud bool Function(T1 value1, T2 value2, T3 value3)
Return true and the HUD widget will be shown or if there is a delayedStart defined then the timer will start. The timer will trigger showing the HUD widget. Use the value of the provider to determine if you should show the HUD or not.


createElement() StatefulElement
Creates a StatefulElement to manage this widget's location in the tree.
createState() → _DelayedHudState3
Creates the mutable state for this widget at a given location in the tree.
debugDescribeChildren() List<DiagnosticsNode>
Returns a list of DiagnosticsNode objects describing this node's children.
debugFillProperties(DiagnosticPropertiesBuilder properties) → void
Add additional properties associated with the node.
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed.
toDiagnosticsNode({String? name, DiagnosticsTreeStyle? style}) DiagnosticsNode
Returns a debug representation of the object that is used by debugging tools and by DiagnosticsNode.toStringDeep.
toString({DiagnosticLevel minLevel =}) String
A string representation of this object.
toStringDeep({String prefixLineOne = '', String? prefixOtherLines, DiagnosticLevel minLevel = DiagnosticLevel.debug}) String
Returns a string representation of this node and its descendants.
toStringShallow({String joiner = ', ', DiagnosticLevel minLevel = DiagnosticLevel.debug}) String
Returns a one-line detailed description of the object.
toStringShort() String
A short, textual description of this widget.


operator ==(Object other) bool
The equality operator.